Yeah, someone want to give the low down on these?
I've been a trackball user for many years. I've been only a finger-control baller, as opposed to a thumb-control baller. My favorite is the Logitech Cordless Optical Trackman, but Logitech discontinued it a couple years ago, so I've been looking at alternatives. Consequently the Kensington Slimblade is a finger-control trackball.
The Slimblade has a large-ish ball in the middle, with 4 buttons arranged around it. With Windows or OS X, there's a driver that allows you to map any of the 4 buttons to pretty much anything. If you chord the top two or the bottom two buttons, each chord can be set to something. From my reading, I know that the 4 buttons will work with the various Linux GUIs "out of the box". Also, the latest driver for Windows (and I think OS X) will allow per application mapping of the 4 buttons and 2 chords.
There is no separate scroll-wheel or dial/ring (like on the Expert Mouse), but the scroll function is accessible by twisting the ball. I find it works best if I use my thumb and middle finger and lightly pinch the ball right where it sticks up and scrolling works effortlessly. One drawback of this twisting motion is if I'm trying to scroll vigorously, the mouse pointer will start moving around.
Speed and acceleration of the mouse pointer is available in the driver (Win and OS X), and a slightly more nebulous speed control for scrolling is available. I do wish there was a setting for the number of lines that a scroll step jumps -- this can be set in the Mouse Control Panel in Windows, but it won't stick between reboots.
For me, the most comfortable way for me to control the Slimblade is by resting my hand on top of the ball, so that the part of my middle and ring fingers closest to the palm of my hand is resting on the very top. This gives me good control the ball. I can rest my thumb on the lower left button (mapped as LMB), and my pinky rests on the upper right button (mapped as RMB). I have the upper left set as "browser back" and the lower right as "enter". This position allows me to easily shift to the scroll pinch and back with only a small movement of my hand.
I can't really compare the Slimblade to any of the CST trackballs since I've never used one, but I really like how flat the Slimblade is. I'm quite certain I wouldn't like the higher wrist/hand angle needed for the CST trackballs. I didn't like the higher angle with the Expert Mouse. Also, the CST trackballs only have 3 buttons, without additional mods. Even then, I find myself wishing for a few more buttons on the Slimblade. The Cordless Optical Trackman had 8 discrete buttons, including the button on the scrollwheel.
Is it worth $60? I think so. It's not solid and heavy. It's pretty light and plasticky, but that's not a bad thing in this case. Just don't turn it upside-down without having a hand over the ball, since it just sits in its pocket.
I don't think the Slimblade is the best finger-control trackball, but it's pretty good. Since it normally goes for $90-$100, I think $60 is a good price.
